Switch arrangement for electronic organs



Oct. 30, 1962 J. E, HoLT 3,060,784

swITCH ARRANGEMENT FCR ELECTRONIC oRCANs Filed July 17, 1959 2 Sheets-Shes 0 76 l' EL 7gg INVENTOR.

Oct. 30, 1962 J. E. HoLT 3,060,784

' SWITCH ARRANGEMENT FOR., ELECTRONIC oRGANs Filed July 17, '1959 2 sheets-sheet 2 Il llll Illll IN VENTOR.

3,060,784 SWITCH ARRANGEMENT FOR ELECTRONIC ORGANS `'lohn E. Holt, Tonawanda, N.Y., assignor to The Wurlitzer Company, Chicago, Ill., a corporation of Ohio Filed July 17, 1959, Ser. No. 827,841 4 Claims. (Cl. 84-423) This invention relates generally to operating mechanisms for electronic organs and more particularly to organ key operated electrical switch arrangements.

The switch arrangement of the present invention is especially useful when it is desired to strike an electronically produced musical note, such as for example would be desired in playing an electronic organ. A common practice in switch arrangements of the type described involves utilization of the movement of the organ key to close an electrical circuit through la mechanical linkage coupling the electrical circuit to the organ key. Use of such a mechanical linkage, of course, predisposes an organ so constructed to frequent servicing, required in order to vmaintain the mechanical linkages in proper adjustment. It is, therefore, an object of the present invention to provide an improved switch arrangement for electronic organs which is directly actuated by the organ key and which requires less frequent servicing.

Another object of the invention is to provide a more reliable switch arrangement for electronic organs.

Yet another object of the invention is to provide a switch arrangement for electronic organs by the use of which the desired musical note can be struck While the appropriate percussion is simultaneously actuated.

A further object of the invention is to provide an improved switch arrangement for electronic organs which is simply constructed Iand which is economical to manufacture.

Additional objects and features of the invention pertain to the particular structure and arrangements whereby the above objects are attained.

The structure in accordance with the invention includes an apertured switch arm which is `adjustably mounted to an organ key in order to relocate a moveable contact between two iixed contacts, the xed and moveable contacts being fastened to a circuit board which is disposed rearwardly in spaced-apart relationship from the organ key.

The invention, both to its structure and mode of operation, will be better understood by reference to the following disclosure and drawings forming a part thereof, wherein:

FIG. 1 is a perspective view of an electronic organ key associated with a switch arrangement in accordance with the present invention;

FIG. 2 is a perspective View of the fixed and moveable contacts and the apertured switch arm used in the switch arrangement of FIG. 1;

FIG. 3 is a fragmentary view of the contacts of FIG. 2, showing the contacts mounted in the circuit board and extending through the guide board;

FIG. 4 is a fragmentary perspective view of the guide board used in FlG. 3;

FIG. 5 is an elevational view through the section 5 5 of FIG. 1;

FIG. 6 is an elevational side view in partial cross section of the showing of FIG. 1, illustrating the switch arrangement in its normal or rest position; and

FIG. 7 is an elevational side view in partial cross section of the switch arrangement of FIG. 1, illustrating the switch arrangement in its operating position.

Referring now in detail to the drawings, specifically to FIG. 1, a conventional organ key 10 is shown pivotally mounted to a balance rail 12 by means of a balance rail pin 14. Balance rail 12 is integrally joined to a keybed 16 which extends across the body of an electronic organ.

Advantageously, an angled bracket 13 is secured to the rearward end of balance rail 12 in order that a tension spring 2d can be extended between the free end of bracket 18 and a nail 22 that is driven into key lll. Spring 2@ serves to bias the keyboard end of key 1i) in a vertically upward direction.

In accordance with the invention, a circuit board 24 is disposed rearwardly in spacedaapart relationship from organ key 10 to extend across through the body of the organ. A suitable electric circuit is printed or otherwise suitably Iapplied to board 24; and this circuit, it is to be understood, provides connections such as to the ampliiiers and continuously operating oscillators customarily incorporated in an electronic organ.

An upper, iixed, straight wire contact 26 and a lower, iixed, straight wire contact 28 are secured to circuit board 24, being by way of illustration, electrically connected to signal output and ground respectively. Also secured to circuit board 24 are the free ends of a generally lJ-shaped spring wire contact 36 which is connected to the signal input portion of the circuit carried by board 24. Contact 30 is arranged to make connection normally with the contact 28, being further arranged to be moveable to make electrical connection with contact 26.

The closed portion 32 of moveable contact 30 is preferably upwardly right angularly formed as shown in the several figures. Contact 3d additionally is preferably inwardly tapered toward the apexes of the right angular bend. Other useful configurations of contact 30 will, of course, suggest themselves to those skilled in the art.

An insulating guide board 34 is disposed between circuit board 24 and key 10, as by being mounted in spaced-apart relationship from board 24 by means of interconnecting struts 36. Fastener 38 may be employed to secure struts 36 rmly in place.

As best shown in FIG. 4, guide board 34 is provided with a vertical aperture or slot 40 which is adapted to pass the upper iixed contact 26. Board 34 is also provided with a smaller downwardly opening vertical aperture or recess 42 aligned vertically beneath aperture 40 in order to pass the lower iixed contact 23. Straddling the aperture 42 are downwardly opening vertical apertures or slots 44 and 46 which are adapted to pass the leg portions of moveable contact 30. It will be apparent that the several apertures in guide board 34 tend to keep the contacts 26, 28, and 30 in proper alignment, additionally insuring spaced-apart or insulating relationship between the several contacts.

In order to implement movement of contact 30 from connection with contact 28 to connection with contact 26, a longitudinally zigzag switch arm 48 is fastened adjacent to the end of key 10 by means of a screw Si); Advantageously, switch arm 4S may be adjustably positioned by means of a screw 52. Switch arm 48 extends beyond the end of key ltl to engage the leg portions of contact 30, switch arm 48 being appropriately provided with a rectangular aperture 54 adjacent to its free end in order to pass and thereby avoid interference with the xed contacts 26 and 28. Arm 48 may be provided with its zigzag shape and with aperture 54 by fabrication according to a metal stamping process.

While the striking of the musical note is achieved through contacts 26, 2S and 30, it is sometimes desirable to actuate simultaneously the percussion effects of the organ notes. Accordingly, an electrically conductive, substantially L-shaped switch arm 56 is secured to key 10 forwardly of switch arm 48 by means of a screw 58, arm 56 being adjustably positioned by means of a screw 60.

The free end of switch arm 56 has aliixed to its np- Wardly turned end a Whisker Wire contact 62 that extends between longitudinally disposed conductors 64 and 66. Conductors 64 and 66 are preferably associated respectively with power and the percussion circuit, being positioned in the organ body by means of a metal channel 68. Conductors 64 and 66 are secured to channel 68 by means of an intervening insulation strip 70.

Advantageously, channel 68 is provided with an aperture 72 whereas insulating strip 70 is provided with an aperture I4 of smaller diameter than aperture 72. Apertures 72 and 74 appropriately pass the free end of contact 62. This arrangement is best shown in FIG. 5.

If desired, a felt stop 76 may be adhered to the bottom surface of channel 68 so as to provide a cushioned engagement between the key lil and channel 68.

The angled element '78 extends across the body proper of the organ slightly rearwardly of switch arm 56 in order to support an insulation board 86. Board lill has affixed to one of its sides a capacitor 82 which is connected in series with a resistor 84. Resistor 84, in turn, is connected to a flexible conductor 86. Conductor 86 is preferably a helical, electrically conductive spring connected to the fixed end of switch arm 56 by a soldered connection 88 or other suitable means.

As will become apparent, the functional elements hereinabove described are advantageously disposed behind the front plate @il of the organ keyboard in accordance with the showing of FIGS. 6 and 7. Additionally, it will be recognized that a switch arrangement, such as has been described, is associated with each of the organ keys displayed in the keyboard. insofar as these duplicate arrangements are illustrated in the drawings, like numerals have been used to denote like elements, the suffix letters La b, etc. being applied to the duplicate members.

Having thus described one construction of the invention, 4it is important now to state how the illustrated ernbodiment operates. The rest or normal configuration illustrated in FIG. 6, moveable contact Sil makes connection with the grounded lixed contact 28 whereas Whisker contact 62` makes connection with power input conductor 64 through the contact 62, the switch arm 56, the flexible conductor 36 and the resistor 84 to the capacitor 32. Furthermore, spring 2t) biases the organ key l@ upwardly against the felt stop 76.

However, when the organ key 1t) is depressed in the general direction of arrow 92 (FIG. 7), zigzag switch arm 48 will lift the closed portion 32 of moveable contact 30 out of engagement with fixed contact 28 and into connection with output circuit contact 26 thereby connecting the input signal circuit to the output circuit through the moveable contact.

Simultaneously, Whisker contact 62 will be lowered'to make connection with percussion output conductor 66; and accordingly, capacitor 62 (having been charged, when an accompanying percussion switch is on) will discharge through resistor 84 to control amplifier conduction to effectuate appropriate percussion.

As will be realized, when organ key lll is released, the biasing spring 20 will return key 10 -to its rest position; and with switch arm 43 no longer urging moveable contact 3l) upwardly, the resilient nature of contact 3l)l will cause it to return to its rest position in connection with grounded fixed contact 28. At the same time, Whisker contact 62 will be raised again into connection with power input conductor 64 whereby capacitor 82 will be restored to rest position for charging when the percussion switch 1n on The foregoing descriptions given with particular regard to an electronic organ are not intended to restrict use of the invention. The switch arrangement of the invention nds other uses, as for example in electronic pianos.

The specific example herein shown and described is illustrative only. Various changes in structure will, no doubt, occur Ato those skilled in the art; and these changes l are to be understood as forming a part of this invention insofar as they fall within the spirit and scope of the appended claims.

The invention is claimed as follows:

l. A switch arrangement for electronic musical instruments comprising: a key depressible again a bias; circuit means located rearwardly of said key; at least one fixed contact extending from said circuit means toward said key; a moveable contact fastened to said circuit means to extend towards said key in operable relationship with said fixed contact; a first switch arm fastened to and extending beyond the rear end of said key to reposition said moveable contact in response to depression of said key; a pair of conductors extending in parallel relationship transversely of said key spaced-apart therefrom forwardly of said first switch arm; a second switch arm fastened to said key forwardly of `said first switch arm in operable association with said conductors; and a wire contact extending from said second switch arm between said conductors, whereby depression of said key relocates said wire contact from connection with one of said conductors to connection with the other of said conductors simultaneously with relocation of said moveable contact.

2. A switch arrangement 'for electronic musical instruments comprising: a key depressible against a bias; circuit means located rearwardly of said key; at least one lixed Contact extending from said circuit means toward said key; a generally U-shaped moveable contact fastened to said circuit means to extend its closed portion toward said key in operable relationship with said fixed contact; a zigzag switch arm fastened to and extending beyond the rear end of said key to reposition said moveable contact in response to depression of said key; a pair of conductors extending in vertically aligned, parallel relationship transversely of said key spaced-apart therefrom forwardly of said zigzag switch arm; a generally L-shaped switch arm fastened to said key forwardly of said zigzag switch arm in operable association with said conductors; a Whisker wire contact extending from said L-shaped switch arm between said conductors; and capacitor means connected to said L-shaped switch arm, whereby depression of said key relocates said Whisker contact from connection with one of said conductors to connection with other of said conductors allowing discharge of said capacitor means simultaneously with relocation of said moveable contact.

3. A switch arrangement for electronic musical inst-ruments comprising: a key depressible against a bias; circuit means located rearwardly of said key; an insulating guide board interposed between said key and said circuit means; at least one fixed contact extending through said guide board from said circuit means toward said key; a generally U-shaped moveable contact fastened to said circuit means passing through said guide board to extend its closed portion toward said key in operable relationship with said fixed contact; a zigzag switch arm adjustably fastened to and extending beyond the rear end of said key to reposition said moveable contact in response to depression of said key, said switch arm having an aperture disposed near its free end adapted to pass the free end of said fixed contact; a pair of conductors extending in vertically aligned, parallel relationship transversely of said key spaced-apart therefrom forwardly of said zigzag switch arm; a generally L-shaped switch arm fastened to said key forwardly of said zigzag switch arm in operable association with said conductors; a Whisker wire contact extending from said L-shaped switch arm between said conductors; and capacitor means flexibly connected to said L-shaped switch arm whereby depression of said key relocates said Whisker contact from connection with one of said conductors to connection with other of said conductors allowing discharge of said capacitor means simultaneously With relocation of said moveable contact.

4. A switch arrangement for electronic musical instruments comprising: a key depressible against a bias; circuit means located rearwardly of said key; an insulating guide fev board interposed between said key and said circuit means, said guide board having a pair of vertically aligned xedcontact-passing apertures and 4a pair of moveable-contactpassing apertures straddling said iixed-contact-passing apertures; a pair of straight wire xed contacts extending through said guide board from said circuit means toward said key in vertically aligned, parallel relationship; a generially U-shaped moveable spring wire contact fastened at its ends to said circuit board and passing through said guide board to extend its upwardly formed, closed portion toward said key between said fixed contacts; a transversely zigzag switch arm adjustably fastened at one end to said key and extending beyond the rear end of said key to reposition said moveable contact from connection with one of said fixed cont-acts to connection with the other of said xed contacts in response to depression of said key, said switch arm having a rectangular aperture disposed near its free end adapted to pass the free ends of said -iixed contacts; a pair of conductors extending in vertically aligned, parallel relationship transversely of said key spaced-apart therefrom forwardly of said zigzag switch arm; a generally L-shaped switch arm fastened to said key forwardly of said zigzag switch arm in operable association with said conductors; a Whisker Wire contact extending from said L-shaped switch :arm between said conductors; and capacitor means flexibly connected to said 6 L-shaped switch arm, whereby depression of said key relocates said Whisker contact from connection with one of said conductors to connection with the other of said conductors allowing discharge of said capacitor means simultaneously with relocation of said moveable contact.

References Cited in the file of this patent UNITED STATES PATENTS 2,049,616 Lilja Aug. 4, 1936 2,176,525 Firestone Oct. 17, 1939 2,250,065 Koehl July 22, 1941 2,489,497 Oswald Nov. 29, 1949 2,513,415 Larsen July 4, 1950 2,558,659 Mork June 26, 1951 2,573,453 Knos Oct. 30, 1951 2,573,895 Evett Nov. 6, 1951 2,577,468 Knos Dec. 4, :1 2,630,503 Larsen et al Mar. 3, 1953 2,714,145 Larsen July 26, 1955 2,785,238 Bissonette i Mar. 12, 1957 2,953,055 Hanert Sept. 20, 1960 FOREIGN PATENTS 479,185 Italy Mar. 18, 1953 816,061 Great Britain July 8, 1959 

